POTENTIAL FOR FARMING EDIBLE SEAWEEDS IN DENMARK, FAROE ISLANDS AND GREENLAND

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1 AARHUS UNIVERSITY POTENTIAL FOR FARMING EDIBLE SEAWEEDS IN DENMARK, FAROE ISLANDS AND GREENLAND Susse Wegeberg Challenges Denmark Faroe Islands Native edible species Cultivation performed Other potential species Methods Greenland Denmark (Baltic Sea Area) (Nielsen et al. 1996) Number of macroalgae species 375 Rhodophyta 160 Phaeophyceae 125 Chlorophyta 90 Conditions of challenge in Denmark Ratio (R:P:C) 1.78 : 1.39 : 1.00 DK R:P index ~ 1.28 Cold temperate regions: R:P index ~ 1.1 Tropical regions: R:P index ~ 4.3 (Lüning 1990) Lack of suitable substratum Relatively small and patchy occurrences of natural seaweed stocks high work load to get feed stock Farming seaweeds make sense 1

2 Salinity The impact of decreasing salinity Submergens The impact of decreasing salinity Decline in species number/distribution Rule of thumb: decrease of 10 psu the number of red algal species is halved The impact of decreasing salinity Depauperation of thallus 325 <100 Nielsen et al

3 Species cultivated in Denmark (on trial) Ulva lactuca L. Chondrus crispus Stackh. Saccharina latissima (L.) C.E.Lane, C.Mayes, Druehl & G.W.Saunders Ulva lactuca From presentation by PD Jensen, Bioenergidag 2008 Photos: Ud & Se

4 Saccharina latissma Great Belt (Birkeland 2009) Limfjorden (Wegeberg 2010) Kattegat, Dyngby (Marifood Aps.) January March Limfjord Photo: Jan Bangsholt May Ref. From Birkeland (2009) April Winter 2010 Photo: Jan Bangsholt 4

5 Marifood Aps. Photos: Marifood Aps. Relatively deep location Early on-grow in sea Manipulated sporulation Iodine In S. latissima from Marifood Aps. the iodine content is app. 10 % of the iodine in Chinese kelp Iodine intake limit: 1100 µg day -1 From Teas et al. (2004) Edible seaweed species in Denmark Species farmed in DK Potential species? Ulva lactuca L. Codium fragile (Suringar) Har. Chondrus crispus Stackh. Osmundea truncata (Kütz.) Saccharina latissima (L.) K.W.Nam & Maggs C.E.Lane, C.Mayes, Druehl & Palmaria palmata (L.) Kuntze G.W.Saunders Porphyra umbilicalis (L.) Kütz. Faroe Islands Challenges Native edible species Cultivation performed Other potential species Methods 5

6 Faroe Islands (Tittley et al. 2005) Number of macroalgae 260 Rhodophyta 112 Phaeophyceae 86 Chlorophyta 62 Ratio (R:P:C): 1.80 : 1.39 : 1.00 R:P index: 1.3 Challenges ISA - Infectious Salmon Anaemia Ton Furunculosis Legislation 2001 ISA : recognised for the first time in Norway 1996: outbreaks in Canada 1998: outbreaks in Scotland 2000: outbreaks in the Faroe Islands Outbreaks in Chile Alaria esculenta - cultivation trial Elongation rate of Alaria esculenta 2 cm d -1 Ca. 1 m season -1 Photos: Agnes M Mortensen Mortensen et al

7 Potential species: Palmaria palmata Porphyra spp. Cultivation has been succesfully achieved on ropes and in tanks: Ireland (Edwards 2007) Germany (Sylter Algenfarm GmbH & Co.KG ) Porphyra umbilicalis Research in cultivation on neutral spores in Maine, USA Seeding nets with neutral spores of the red alga Porphyra umbilicalis (L.) Kützing for use in integrated multi-trophic aquaculture (IMTA)(Blouin et al. 2007) 7

8 Greenland Challenges Native edible species Greenland (Pedersen 1976) Number of macroalgae 183 Rhodophyta 48 Phaeophyceae 80 Chlorophyta 55 Ratio (R:P:C): 1.00 : 1.67 : 1.15 R:P index: 0.6 Photo: Per Dolmer Short season Low temperatures Ice Early on-grow in sea Deep location for on-grow Open water areas/polynias Potential species in Greenland Paamiut, January 2010 (DMI, COI) Photo: Per Dolmer Photo: Per Dolmer 8

9 Harvest of natural stocks? Wegeberg (2007) Photo: Per Dolmer 9